Multilateral environmental agreements (MEAs) are the backbone of global environmental governance. Their ability to deal effectively with international environmental challenges depends on the problem structure andf the problem solving ability of the regime in question. The success or failure primarily depends on the problem structure, including the degree of political and scientific conflicts and uncrertainty and consensus. However institutional desgin may also matter because it can affect the problem strucrure and increase problem solving ability. Based on experiences with MEAs an international ABR agreement should have robust repoorting/verification proceures, sanctions for non-compliance, assistance for implementation, a strong secretariat, an independent scientific advisory panel and spesific commitments. However, more reserach is needed to judge whether such an institutional set-up is politically feasible for a possible international ABR regime.